P247F

Code

Generic P — Powertrain

Exhaust Gas Temperature Out of Range Bank 2 Sensor 4

Brand: Generic

Type: P — Powertrain

Views: UK: 13 EN: 22 RU: 25

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Malfunction Indicator Lamp (MIL) illuminated
Diagnostic trouble code P247F stored
Possible reduced aftertreatment performance or incomplete DPF/catalyst regeneration
Loss of closed-loop control of aftertreatment functions; possible limp-home mode on some vehicles
No obvious driveability symptoms in some cases
Failed emissions test or increased tailpipe emissions

Retrieve freeze frame and live data with a capable scan tool — note engine load, rpm, vehicle speed and EGT values at fault occurrence
Verify code is current (pending vs confirmed) and check for related codes
Visually inspect wiring and connector for Bank 2 Sensor 4 for damage, corrosion, heat discoloration or exhaust soot ingress
Inspect exhaust and mounting: check for leaks, damaged flanges or signs of local overheating
Wiggle test harness while monitoring live data to find intermittent opens/shorts
Measure heater circuit resistance (if applicable) and compare to factory spec

EGT sensors may be thermocouples (mV output) or NTC/RTD (resistance vs temperature). Verify sensor type in service manual before testing.
Typical operating EGT ranges (approximate and vehicle-dependent): downstream/post-aftertreatment sensors often
A heated EGT sensor’s heater circuit should show low resistance (typically single- to low two-digit ohms) and be supplied with switched battery voltage when enabled — consult vehicle spec.
A true out-of-range condition is where the sensor signal is constant, pegged high/low, outside expected temperature for operating condition, or heater circuit is open/short.
Always compare live data from Bank 2 Sensor 4 to other EGT sensors and to expected values for the observed operating state.

Read and record freeze frame and related codes; disconnect battery only if required by service manual.
Visually inspect sensor, connector, and wiring for damage, heat discoloration, soot or oil contamination. Repair any obvious wiring/connectivity issues.
With a scan tool, monitor Bank 2 Sensor 4 live data while engine is cold, warming and at operating conditions. Note if value changes predictably with temperature and load.
Perform a wiggle test on wiring and connectors while observing live data to find intermittent faults.
Verify heater circuit (if present): disconnect connector, measure resistance at sensor and at ECM harness side; verify power/ground supply at connector with ignition on and heater commanded.
Measure sensor signal (mV or resistance) against service limits while engine is warm. If signal does not change with exhaust temperature or is out of expected range, suspect sensor or wiring.
Inspect exhaust for leaks or physical interference near sensor; repair as needed and retest.
If wiring and supplies are good but signal is still out of range, replace sensor with correct OEM-type part and clear codes.
After repair, perform a drive cycle and recheck for code reappearance and proper EGT behavior. If code returns, proceed to ECM/PCM diagnostics per manufacturer procedures.